fix(developer): kmdecomp virtual character key output

Virtual character keys were being written as garbage, for example:

```
store(store17) [RALT ""] [RALT SHIFT ""] [RALT ""] [RALT SHIFT ''] [RALT SHIFT ""] [RALT SHIFT ""] [RALT SHIFT ""] [RALT SHIFT ""] [RALT SHIFT ""] [RALT ""] [RALT SHIFT ""] [RALT SHIFT ""] [RALT SHIFT ""] [RALT ""] [RALT SHIFT ""] [RALT ""] [RALT ""] [RALT ""] [RALT SHIFT ""]
store(store18) [RCTRL ""] [RCTRL SHIFT ""] [RCTRL ""] [RCTRL SHIFT ''] [RCTRL SHIFT ""] [RCTRL SHIFT ""] [RCTRL SHIFT ""] [RCTRL SHIFT ""] [RCTRL SHIFT ""] [RCTRL ""] [RCTRL SHIFT ""] [RCTRL SHIFT ""] [RCTRL SHIFT ""] [RCTRL ""] [RCTRL SHIFT ""] [RCTRL ""] [RCTRL ""] [RCTRL ""] [RCTRL SHIFT ""]
```

Picked up in regression testing the compiler.